test: disable deprecation warnings on pytest

[lucasmoura]

Why is this needed?

Due to our Xenial support, we have deprecated warnings our pytest tests. Since we are aware of that, we are remove those deprecation warnings when running the command

Test Steps

Run tox -e test and verify that the deprecation warnings are not there anymore

Checklist

• [ ] I have updated or added any unit tests accordingly
• [ ] I have updated or added any integration tests accordingly
• [ ] Changes here need to be documented, and this was done in:

Does this PR require extra reviews?

• [ ] Yes
• [x] No

[github-actions[bot]]

Jira: This PR is not related to a Jira item. (The PR title does not include a SC-#### reference)

GitHub Issues: No GitHub issues are fixed by this PR. (No commits have Fixes: #### references)

Launchpad Bugs: No Launchpad bugs are fixed by this PR. (No commits have LP: #### references)

Documentation: The changes in this PR do not require documentation changes.

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